129012878 has 4 divisors (see below), whose sum is σ = 193519320. Its totient is φ = 64506438.

The previous prime is 129012853. The next prime is 129012883. The reversal of 129012878 is 878210921.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32253218 + ... + 32253221.

It is an arithmetic number, because the mean of its divisors is an integer number (48379830).

Almost surely, 2^129012878 is an apocalyptic number.

129012878 is a deficient number, since it is larger than the sum of its proper divisors (64506442).

129012878 is an equidigital number, since it uses as much as digits as its factorization.

129012878 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 64506441.

The product of its (nonzero) digits is 16128, while the sum is 38.

The square root of 129012878 is about 11358.3835997909. The cubic root of 129012878 is about 505.2942480188.

The spelling of 129012878 in words is "one hundred twenty-nine million, twelve thousand, eight hundred seventy-eight".